[PATCH v2 net-next 04/12] bpf: check for reserved flag bits in array and stack maps

[Alexei Starovoitov]

Suggested-by: Daniel Borkmann <dan...@iogearbox.net>
Signed-off-by: Alexei Starovoitov <a...@kernel.org>
---
 kernel/bpf/arraymap.c | 2 +-
 kernel/bpf/stackmap.c | 3 +++
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c
index bd3bdf2486a7..76d5a794e426 100644
--- a/kernel/bpf/arraymap.c
+++ b/kernel/bpf/arraymap.c
@@ -53,7 +53,7 @@ static struct bpf_map *array_map_alloc(union bpf_attr *attr)
 
        /* check sanity of attributes */
        if (attr->max_entries == 0 || attr->key_size != 4 ||
-           attr->value_size == 0)
+           attr->value_size == 0 || attr->map_flags)
                return ERR_PTR(-EINVAL);
 
        if (attr->value_size >= 1 << (KMALLOC_SHIFT_MAX - 1))
diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c
index 8a60ee14a977..f0a02c344358 100644
--- a/kernel/bpf/stackmap.c
+++ b/kernel/bpf/stackmap.c
@@ -35,6 +35,9 @@ static struct bpf_map *stack_map_alloc(union bpf_attr *attr)
        if (!capable(CAP_SYS_ADMIN))
                return ERR_PTR(-EPERM);
 
+       if (attr->map_flags)
+               return ERR_PTR(-EINVAL);
+
        /* check sanity of attributes */
        if (attr->max_entries == 0 || attr->key_size != 4 ||
            value_size < 8 || value_size % 8 ||
-- 
2.8.0.rc1